Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?
Schema description coverage is 50%: the 'scenario' parameter has a description, but 'categories' does not. The description compensates by listing the category types (demographics, medications, conditions, labs, vitals, allergies, immunizations, encounters) and implying the 'mix' concept, though it omits 'documents' and 'claims' from the wording even though they appear in the enum. The 'scenario' meaning is covered explicitly ('pick one with scenario', with behavior scenarios noted). Given the partial schema coverage and the added clarity about scenario selection, the description goes beyond the schema but stops short of fully matching the enum list, so a 4 is appropriate.
Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.